Introduction to Food Engineering ERT 426 Food Engineering

Introduction to Food Engineering ERT 426 Food Engineering Semester 2 Academic Session 2010/11 BB Lee @ Uni. Map 1

Subtopics Background Food Industry in Malaysia Typical Food Manufacturing Processes Recent Developments in Food Engineering Research 5. Present Trends and the Future of Food Engineering 6. Sociocultural Aspects of Some Critical Points Limiting Progress 1. 2. 3. 4. ERT 426 Food Engineering BBLee@Uni. MAP 2

1. Background �Food engineering is a multidisciplinary field of applied physical sciences which combines science, microbiology, and engineering knowledge for food and related industries. �Food engineering includes, but is not limited to, the application of agricultural, chemical, mechanical, civil and electrical engineering principles in addition to food sciences to food materials. ERT 426 Food Engineering BBLee@Uni. MAP 3

Background �Food Engineers: Ø provide the technological knowledge transfer essential to the cost-effective production and commercialization of food products and services. • When foods are used as raw materials they offer unique challenges. Ø Perhaps the most important concern in food processing is the variability in the raw material. Ø To achieve consistency in the final quality of a processed food, the processes must be carefully designed to minimize variations caused by processing. ERT 426 Food Engineering BBLee@Uni. MAP 4

Background �Food engineering is a very wide field of activities. ØProspective major employers for food engineers include companies involved in food processing, food machinery, packaging, ingredient manufacturing, instrumentation, and control. ØFirms that design and build food processing plants, consulting firms, government agencies, pharmaceutical companies, and health-care firms also hire food engineers. ERT 426 Food Engineering BBLee@Uni. MAP 5

2. Food industry in Malaysia �Malaysia's food industry is as diverse as the multicultures of Malaysia, with a wide range of processed food with Asian tastes. �In 2008, the food processing industry contributed about 10% of Malaysia's manufacturing output. Ø Companies in this industry are predominantly Malaysian-owned. Ø In Malaysia, the food industry is dominated by small and medium scale companies. Ø The major sub-sectors are fish and fish products, livestock and livestock products, fruits, vegetables and cocoa. Information is taken from Malaysian Industrial Development Authority (MIDA) ERT 426 Food Engineering BBLee@Uni. MAP 6

Food industry in Malaysia �It is estimated that the present global retail sales in food products are worth around US$3. 5 trillion, and are expected to grow at an annual rate of 4. 8 per cent to US$6. 4 trillion by 2020. Ø Malaysia's food exports amounted to RM 17. 9 billion in 2008, while imports totalled RM 28 billion. Ø Malaysia remains as a net importer of food. �Malaysia exported food products to more than 200 countries. Ø The main products exported were: 1. cocoa (RM 3 billion), 2. fisheries products (RM 2. 5 billion), 3. margarine and shortening (RM 2. 4 billion) 4. animal feed (RM 1. 2 billion). Information is taken from Malaysian Industrial Development Authority (MIDA) ERT 426 Food Engineering BBLee@Uni. MAP 7

Food industry in Malaysia �Major food imports in 2008 were cereal and cereal preparations, cocoa, vegetables and fruits, dairy products and animal feed. �Raw materials such as cereals and dairy products will continue to be imported for further processing for human consumption as well as for the production of animal feed. Information is taken from Malaysian Industrial Development Authority (MIDA) ERT 426 Food Engineering BBLee@Uni. MAP 8

Food industry in Malaysia �Currently, Malaysia is the largest cocoa processor in Asia and ranks fifth in the world. Ø However, most of the cocoa beans are imported. �Malaysia is one of the world major producers of spices. �In 2008, Malaysia's was ranked as the fifth largest exporter of pepper and pepper-related products (specialty pepper, processed pepper and pepper sauces). Information is taken from Malaysian Industrial Development Authority (MIDA) ERT 426 Food Engineering BBLee@Uni. MAP 9

Food industry in Malaysia �The halal industry in Malaysia provides immense opportunities for Malaysian manufacturers. �With a global Muslim population of about 2 billion, the market for halal food is estimated at US$547 billion a year. �The concept of halal is associated with food products which are of high quality in terms of cleanliness, sanitation and compliance with religious requirements. �Local halal food products can gain easy access into world wide halal markets as Malaysia‘s halal certification is globally recognised. ERT 426 Food Engineering BBLee@Uni. MAP Information is taken from MIDA 10

3. Typical food manufacturing processes �During the last 30 years, the food engineering discipline has evolved to encompass several aspects of food processing. �The diversity of processes typically employed in a food processing plant is illustrated in Figure 1. ERT 426 Food Engineering BBLee@Uni. MAP (Heldman & Singh, 1981) 11

Typical food manufacturing processes �Typical food processes may include: i. sorting and size reduction, ii. transport of liquid foods in pipes, iii. heat transfer processes carried out using heat exchangers, iv. separation processes using membranes, v. simultaneous heat and mass transfer processes important in drying, and vi. processes that may involve a phase change such as freezing. ERT 426 Food Engineering BBLee@Uni. MAP 12

4. Recent Developments in Food Engineering Research �Research in food engineering was initially focused on: Ø the analysis of food manufacturing, Ø the processing and packaging operations, Ø the utilization of agricultural materials and energy, Ø the environmental issues. ERT 426 Food Engineering BBLee@Uni. MAP 13

Recent Developments in Food Engineering Research �During the past two decades, however, chemical engineering and food engineering have shown a dramatic change in their research emphases because of revolutionary developments in three fields: 1. Biotechnology Ø particularly genetic engineering) 2. Computer science and technology Ø applied mathematics and modeling (e. g. , kinetics, neural networks, and fuzzy logic) 3. Material science Ø especially understanding the relations between the molecular structure and functional properties of materials) ERT 426 Food Engineering BBLee@Uni. MAP 14

5. Present Trends and the Future of Food Engineering �Paradigm for Product/Process Development in the 21 st Century: 1. Development of key scientific "knowledge-based" components (e. g. , food properties) 2. Development of quantitative relationships between food properties and quality attributes which should be: • Quantifiable • Reproducible • Relevant 3. Relationships (models) organized in computerbased information systems similar to those available in the chemical industry for thermodynamic properties (e. g. , Aspen). ERT 426 Food Engineering BBLee@Uni. MAP 15

Present Trends and the Future of Food Engineering 4. Application of models in specific developmental tasks 5. Development and utilization of on-line sensing systems for key food properties (eventually similar sensing systems may be feasible for quality attributes as well). ERT 426 Food Engineering BBLee@Uni. MAP 16

Present Trends and the Future of Food Engineering �Emulsification technology is important in the creation of mayonnaise, peanut butter, various full-fat and low-fat spreads, as well as many beverages and flavor preparations. Ø The rheological and diffusional properties of an emulsification process are of fundamental importance as new analytical and instrumental methods are available and mathematical relations relating them to process parameters can be established. ERT 426 Food Engineering BBLee@Uni. MAP 17

Present Trends and the Future of Food Engineering �Emulsion Technology-Based Foods: 1. Objectives of material science research: Ø Control of texture and mouthfeel Ø Control of storage stability and thermal stability Ø Ability to use alternative components to modify nutritional and organoleptic properties 2. Knowledge-based surface properties are : Ø Free surface energy, surface viscosity, dynamic tension, surface elasticity, surface charge Ø Rheological properties Ø Diffusivity of components 3. Quantitative relational models have: Ø Sensory response versus physical properties Ø Physical properties versus temperature, pressure and other variables ERT 426 Food Engineering BBLee@Uni. MAP 18

Present Trends and the Future of Food Engineering 4. Applications: Ø Low-fat spreads using fat mimetics Ø Design of emulsification systems Ø Incorporation of controlled release formulations 5. Relevant new tools: Ø Image analysis (visible, IR, NMR, ESM) Ø Computer-aided simulation of structure Ø New mathematical tools (e. g. , fractal analysis) 6. Current status: Ø The physical aspects have undergone advanced research in key corporate and academic institutions ERT 426 Food Engineering BBLee@Uni. MAP 19

Present Trends and the Future of Food Engineering �A useful way of presenting a material's physical properties is with "State Diagrams, " which can relate them (especially those related to molecular mobility) to temperature and aqueous system concentration. Ø One of their key features is a glass transition line that relates glass transition temperature (Tg) to the given solute's concentration. Ø Recent work at several research centers has developed information allowing construction of these diagrams for multisolute systems and food materials as well. Ø The knowledge of glass transition lines allows the prediction of conditions under which given desirable or undesirable changes are retarded or accelerated. ERT 426 Food Engineering BBLee@Uni. MAP 20

State Diagram for food materials ERT 426 Food Engineering BBLee@Uni. MAP 21

Present Trends and the Future of Food Engineering �Developing Quantitative Relationships Between Physical and Sensory Properties of Syrups: 1. Mouth feel: Ø Sensory thickness is proportional to the shear stress on the surface of the tongue. Ø Sensory smoothness is inversely proportional to the friction force on the tongue. 2. Perception of properties during pouring: Ø Subjective viscosity is related to the bottle-neck area filled by the syrup. Ø Subjective drippiness is related to the normalized instability growth rate (which can be calculated from known physical parameters). 3. Perception of properties during spreading: Ø Sensory viscosity shows a good correlation with the radial growth of a syrup puddle. Ø Sensory smoothness was well correlated with the aspect ratio of the syrup mass. [Aspect ratio = Dmin IDmax , Dmin & Dmax - the minimum & maximum diameters of a spreading puddle] ERT 426 Food Engineering BBLee@Uni. MAP 22

Present Trends and the Future of Food Engineering �The use of enzymes that act specifically on selected substrates or intermediates to eliminate undesirable products or the localization of reactants, catalysts, or antioxidants in portions of food in which a particular reaction may be desirable (e. g. , surface browning). �The requirement for the successful application of these principles lies in developing sound knowledge of the mechanism and kinetics of food reactions. ERT 426 Food Engineering BBLee@Uni. MAP 23

Present Trends and the Future of Food Engineering �Potential Approaches for Controlling Complex Reactions in Foods: 1. Enzymes: Ø Using substrate specificity of selected enzymes reactions may be directed to produce desired products (e. g. , lipoxidases to control oxidation derived compounds according to Vliegenthart of Utrecht and Pratt of Purdue). Ø Enzymes may also be added to remove undesirable products or intermediates. 2. Other catalysts or inhibitors: Ø Reactions may be directed by catalyzing or inhibiting specific reaction steps (e. g. , p. H control in browning reactions). ERT 426 Food Engineering BBLee@Uni. MAP 24

Present Trends and the Future of Food Engineering 3. Addition of substrates or intermediates: Ø Reactions may be modified by adding specific precursors of desired end products. 4. Localization of reactants or catalysts: Ø As in liposomes containing proteases in cheese ripening (Kirby) 5. Controlling environmental factors: Ø Different steps may have different activation energies or reactants of differing solubility; regulating temperature, pressure, or water activity will control reactions. ERT 426 Food Engineering BBLee@Uni. MAP 25

6. Sociocultural Aspects of Some Critical Points Limiting Progress 1. Reluctance of consumers to accept the following: Ø Compositions perceived as unnatural (even those that are natureidentical). Ø Ingredients created or modified by genetic engineering. Ø Foods processed by nontraditional energy input such as ionizing radiations. 2. Inadequate public understanding of the interface between diet and health resulting in temporary interests that often divert food product development from more sound long-term objectives. ERT 426 Food Engineering BBLee@Uni. MAP 26